Legendary Giant Sloth Sought by Scientists In Amazon Rain Forest

By MALCOLM W. BROWNE

Published: February 8, 1994

AN American biologist and a team of scientists, technicians and Indian guides are preparing to penetrate the trackless rain forest of western Brazil in pursuit of a South American counterpart of the fabled Himalayan yeti.

The object of this quest, headed by Dr. David C. Oren, an American ornithologist employed by the Brazilian Government, is an animal Dr. Oren believes to be a human-size ground sloth, belonging to a family thought by paleontologists to be long extinct.

Accounts by Indians of the Amazon region describe the elusive animal as terrifying and dangerous, physically powerful and equipped with some kind of chemical defense capable of paralyzing opponents. Dr. Oren, a staff scientist at the Goeldi Natural History Museum in Belem, Brazil, said by telephone that he had conducted more than 100 interviews in the last nine years with Indians and rubber tappers who told of having had contacts with the creature.

Dr. Oren acknowledges that he has had trouble persuading other scientists of the possibility that the creature is anything more than a local myth.

Among the American biologists he has sought to interest in the search is Dr. Malcolm C. McKenna, a paleontologist at the American Museum of Natural History in New York City. Dr. McKenna is dubious.

"While there is always a chance of discovering some previously unknown large animal somewhere in the world, just as it is possible to discover some new island in mid-ocean," Dr. McKenna said, "the likelihood is too small to draw me away from my work here. You can't just go chasing each rumor of a sasquatch or yeti.

"On the other hand, discoveries of large new animals have sometimes surprised scientists: a large ungulate in post-war Vietnam; the okapi, discovered in Africa in 1900, a new peccary in the South American Chaco region believed to be extinct since the Pleistocene epoch. You never know."

But Dr. McKenna said it would take more than word-of-mouth accounts to convince scientists of the reality of a ground sloth living in the Amazon Basin. "I think scientists will insist on seeing at least a chunk of it," he said. "Even a photograph won't do."

Dr. Oren agrees that to convince skeptics he would have to bring the creature back, dead or alive.

"We'll be bringing tranquilizing dart guns," he said, "although it may be difficult to use them effectively." Most Indian accounts of the creature describe it as having an extremely tough skin that cannot be easily penetrated.

"That description tallies with fossil remains of a family of extinct ground sloths known as the mylodontids," he said. "These animals had dermal ossicles -- bony armor plating embedded in the skin."

Reports have long circulated about a "mapinguari," a legendary and terrifying manlike creature of the vast Amazon rain forest, but when scientists took an interest at all, Dr. Oren said, they tended to guess that the animal, if it existed, might be some kind of primate.

"But when I began hearing accounts of a creature with shaggy red hair, backward-turned feet and a monkeylike face, I realized that witnesses might have encountered a ground sloth, closely related to extinct giant sloths known only from their fossils."

Three families of sloths are known, and only two genuses, both of them tree dwellers, are known to have survived to the present day, Dr. Oren said. The common three-toed sloth is a lethargic creature that seems to live in slow motion, and is considered a family member of the megatheriids, known mostly from fossils.

The much rarer modern two-toed sloth, a surviving member of the megalonychid family, is less "slothful," Dr. Oren said, and can move swiftly and forcefully if threatened. The third family of sloths, the extinct, ground-dwelling mylodontids, grew to the size of large bears and were apparently very active.

The mapinguari, as Indians call the supposed forest creature, is apparently smaller than fossil members of the family, standing only about six feet tall when walking on its hind feet, but weighing some 500 pounds, and with jaws and feet powerful enough to rip palm trees apart. The creature is said to subsist largely on palm hearts and other vegetable delicacies of the rain forest. Agreement on Appearance

The mapinguari is also described as having a thunderous voice that can sound quite human, and that has deceived human visitors to its habitat into thinking that another human was nearby.

Purported sightings of the creatures over a wide area generally agree on its appearance, Dr. Oren said, including descriptions of a ridge of manelike fur along the animal's neck and back.

"The Indians are very frightened of it, but some of them are anxious to capture one to prove to outsiders that it exists," Dr. Oren said. "Ten of these Indians will accompany our expedition."

Provided Dr. Oren and his group obtain necessary government permits in time, they hope to set out during the first week of March, and expect to remain in the rain forest for about a month. To reach the interior of the State of Acre near the point where the frontiers of Brazil meet those of Peru and Bolivia -- one of the regions where sightings have been reported -- the group will travel to an Indian village, then up-river by boat, and then by foot, at least two days' march into the trackless forest. The creature is apparently never sighted along waterways where there is human habitation, but only in the depths of the forest.

A major motive for the search, Dr. Oren said, is to demonstrate that a large number of species in the Amazon Basin remain unknown to science but are nevertheless worthy of protection and conservation.

"My whole reason for being in the Amazon as a scientist," Dr. Oren said, "is to survey its enormous variety of species. If this ground sloth exists, it may be the largest land mammal in South America, and yet it is still unknown to science. If we find it, we will have proof that there are vast biological riches here that still await discovery."